Thermally-induced SME mechanism

Molecular thermally-induced SME mechanism of traditional SMPU... 

In order to explain the mechanism of thermally-induced shape memory behavior, a molecular model of the thermally-induced SME mechanism of BIN-SMPUs is presented in Fig. 7.23. 

Fig. 4 Molecular mechanism of the thermally-induced SME. Ttrans is the thermal transition temperature of the switching phase (adapted from [40] Copyright Wiley-VCH Verlag GmbH Co. KGaA. Reproduced with permission)...

Shape memory mechanism of thermally-induced SME of BIN-SMPUs. 

Abstract This chapter introduces the moisture-induced shape memory effect (SME) observed in supramolecular shape memory polymers, particularly shape memory polyurethane (SMPU), containing pyridine moieties. The moisture absorption of polyurethane networks containing pyridine moeties (PUPy) is discussed followed by an investigation into the effect of relative humidity (RH), temperature, BINA content and MDI-BDO content. The induence of moisture absorption on both the thermal properties and the dynamic mechanical properties of SMPUs is also described, along with the moisture-induced SME mechanism. 

Abstract This chapter presents the thermaUy-indnced shape memory properties of supramolecular shape memory polyurethane (SMPU) containing pyriine moieties, and compares them with those of other types of SMPU. llie influence of the BINA content and the MDI-BDO content on the thermally-induced shape memory effects (SMEs) of these SMPUs are discussed, including shape fixity, shape recovery and shape recovery stress, as well as the temperature-dependent strain recovery process. A description and analysis of the mechanism of thermaUy-induced SMEs is also provided, covering the effect of temperature and pyridine content on the hydrogen bonds present in SMPUs. 

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